Is Hawaii the Result of a Big Bang?

by Stephen James O'Meara

Does Hawaii, the burning jewel of the North Pacific, have an extraterrestrial origin? It's possible, says Andrew Glikson from the Australian National University. He believes that an asteroid impact may have created the hot spot that supplies Hawaii with its lava. Hot spots, mysterious bubbles of molten rock in Earth's mantle (the semimolten region between earth's core and crust) seem to spring up out of nowhere to create new landforms. An asteroid impact would solve the mystery of hot spots by giving them a beginning.

Actually, the idea of linking space rocks and lava goes back to at least the 1960s. But recent debates are burning around controversial computer models that show how an asteroid can create a hot spot. Jay Melosh, a crater expert from the University of Arizona, remains doubtful. He says that there is no clear physical evidence of a link between space rocks and lava.

Still, the computer models do come up with ways that an impact could cause, or at least speed up, a volcanic eruption. And those who support the idea are quick to point out one simple fact: Geologists have not come up with a better explanation for how Earth's hot spots got started.

Vocabulary

asteroid:

One of the thousands of small planets that orbit the Sun, mostly in the region between Mars and Jupiter. Asteroids range in size from about one mile to several hundred miles in diameter.

Activity

What layers of Earth are affected by earthquakes and by volcanoes?[anno: Earthquakes take place on the crust. Volcanoes involve the crust and the mantle. Landslides involve the crust.]

What causes earthquakes and volcanoes?[anno: In an earthquake, pressure building up under Earth's crust causes sections of the crust to shift. Pressure beneath igneous rock sometimes builds up until the igneous rock is pushed through Earth's crust, resulting in a volcano.]

Earth is in a constant state of change. What are some of the benefits of this state? What would happen if Earth's surface never changed? Write a paragraph explaining some of the benefits of Earth's changing surface.[anno: Answers will vary but could include that the recycling of rock and other nutrients through earthquakes and volcanoes keeps Earth's surface supplied with new material. Students might mention that the creation of new land through oceanic volcanoes gives people more land to live on.]